Determining the Statistical Relationship between the S20 Brittleness Index and Schmidt Hardness of Rocks

Year 2019, Volume: 7 Issue: 4, 839 - 846, 04.12.2019

Hakan Özşen , Abdullah Uysal Arif Emre Dursun

https://doi.org/10.36306/konjes.654957

Cited By: 1

Abstract

Determination of the brittleness of rocks is considered as an important preliminary design tool in different mining applications. The brittleness value is an important rock parameter used in the excavation and drilling of rocks. Schmidt's hardness is an inexpensive and easy-to-use surface hardness measure that is commonly used to determine the mechanical properties of rocks, such as strength, cuttability (linear and circular), and permeability. In this study, the S20 brittleness index values were determined by using NTNU model to determine the brittleness values of the rocks which was developed by Blindheim and Bruland (1998). The aim of this study was to investigate the relationship between the S20 brittleness index and Schmidt hardness (RL) values statistically. For this purpose, Schmidt hardness tests and S20 brittleness index tests on 7 different rock samples with different strength properties were performed. Schmidt hardness test values and S20 brittleness index values were statistically evaluated and correlated with SPSS. As a result of this evaluation, it was determined that there was a strong correlation between Schmidt hardness and S20 brittleness index values.

Keywords

S20 brittleness index, Schmidt hardness, statistical estimation, rock mechanics

KAYAÇLARIN S20 KIRILGANLIK İNDEKSİ İLE SCHMIDT SERTLİĞİ ARASINDAKİ İLİŞKİNİN İSTATİSTİKSEL OLARAK BELİRLENMESİ

Abstract

Kayaçların kırılganlığının belirlenmesi farklı madencilik uygulamalarında önemli bir ön tasarım aracı olarak kabul edilmektedir. Kırılganlık değeri kayaçların kazısında ve delinebilirliğinde kullanılan önemli bir kaya parametresidir. Schmidt çekici sertliği ise kayaların dayanım, kesilebilirlik (doğrusal ve dairesel) ve delinebilirlik gibi mekanik özelliklerini belirlemek için yaygın olarak kullanılan ucuz ve kolaylık sağlayan bir yüzey sertliği ölçüsüdür. Bu çalışmada, kayaçların kırılganlık değerlerini belirlemek için Blindheim ve Bruland’ın (1998) geliştirdiği S20 kırılganlık indeksinin NTNU modeli kullanılmıştır. Burada amaç, kayaçların S20 kırılganlık indeksi ile Schmidt sertliği (RL) değerleri arasındaki ilişkinin istatistiksel olarak araştırılarak yeni bir tahmin yöntemi geliştirmesidir. Bunun için, farklı dayanım özelliklerine sahip 7 farklı kayaç numunesi üzerinde S20 kırılganlık indeks deneyi ile Schmidt çekici sertlik deneyleri yapılmıştır. Schmidt çekici sertliği değerleri ile S20 kırılganlık indeksi değerleri “SPSS” programı yardımıyla istatistiksel olarak değerlendirilmiş ve korelasyon yapılmıştır. Bu değerlendirme sonucunda Schmidt çekici sertliği değerleri ile S20 kırılganlık indeksi değerleri arasında yüksek korelasyonlu bir ilişki olduğu belirlenmiştir.

Keywords

S20 kırılganlık indeksi, Schmidt sertliği, istatistiksel tahmin, kaya mekaniği

References

• Altındağ, R., 2002, “The Evaluation of Rock Brittleness Concept on Rotary Blasthole Drills” Journal of the Southern African Institute of Mining and Metallurgy, Vol.102, pp.61-66.
• Aydın, A., Basu, A., 2005, “The Schmidt Hammer in Rock Material Characterization”, Engineering Geology, Vol.81, pp.1-14.
• Bilgin, N., Seyrek, T., Shahriar, K., 1990, “Roadheaders Glean Valuable Tips for Istanbul Metro”, Tunnels and Tunnelling International, Vol.22, No.10, pp.29-32.
• Bilgin, N., Dincer, T., Copur, H., 2002, “The Performance Prediction of Impact Hammers from Schmidt Hammer Rebound Values in Istanbul Metro Tunnel Drivages”, Tunnelling and Underground Space Technology, Vol.17 (3), pp.237-247.
• Blindheim, O.T., Bruland, A., 1998, “Boreability testing, Norwegian TBM tunneling 30 years of experience with TBMs in Norwegian tunneling”, Norwegian Soil and Rock Engineering Association Publication, Vol.11, pp. 29-34.
• Copur, H., Bilgin, N., Tuncdemir, H., Balci, C. 2003., “A set of Indices Based on Indentation Test for Assessment of Rock Cutting Performance and Rock Properties”, Journal of the Southern African Institute of Mining and Metallurgy, Vol. 103, No.9, pp.589-600.
• Dahl, F., 2003., “The Suggested DRI, BWI, CLI standards. NTNU”, Anglesggsdrift, Trondheim, Norway.
• Dahl, F, Bruland, A, Grov, E, Nilsen, B, 2010, “Trademarking the NTNU/SINTEF drillability test indices”, Tunnels and Tunnelling International, Vol.4, pp.44-46.
• Dahl, F, Bruland, A, Jakobsen, P.D., Nilsen, B., Grov, E., 2012, “Classifications of properties influencing the drillability of rocks, based on the NTNU/SINTEF test method”, Tunnelling and Underground Space Technology, Vol.28, pp.150-158.
• Dursun, A.E., Gokay, M.K., 2016, “Cuttability Assessment of Selected Rocks through Different Brittleness Values”, Rock Mechanics and Rock Engineering, Vol.49, pp.1173-1190.
• Farmer, I.W., Hignett, H.J., Hudson, J.A., 1979, “The Role of Geotechnical Factors in the Cutting Performance of Tunneling Machines in Rocks”, In: Proceedings of the Fourth International Congress on Rock Mechanics of the ISRM, Montreux, pp. 371–377.
• Goktan, R.M., Gunes, N., 2005, “A Comparative Study of Schmidt Hammer Testing Procedures with Reference to Rock Cutting Machine Performance Prediction”, International Journal of Rock Mechanics and Mining Sciences, Vol.42, pp.466-477.
• Howarth, D.F., Adamson, W.R., Berndt, J.R., 1986, “Correlation of Model Tunnel Boring and Drilling Machine Performances with Rock Properties”, International Journal of Rock Mechanics and Mining Science &Geomechanics Abstracts, Vol.23, pp.171–175.
• Hucka, V., Das, B., 1974, “Brittleness determination of rocks by different methods”, International Journal of Rock Mechanics and Mining Science, Vol.11, pp.389–392.
• Kahraman, R., 1999, “Rotary and Percussive Drilling Prediction Using Regression Analysis”, International Journal of Rock Mechanics and Mining Sciences, Vol.36, pp.981–989.
• Kahraman, R., Balcı, C., Yazıcı, S., Bilgin, N., 2000, “Prediction of the Penetration Rate of Rotary Blast Hole Drills Using a New Drillability Index”, International Journal of Rock Mechanics and Mining Sciences, Vol.37, pp.729–743.
• Kahraman, S., 2002, “Correlation of TBM and Drilling Machine Performance with Rock Brittleness”, Engineering Geology., Vol.65, pp.269-283.
• Kahraman, S., Bilgin, N., Feridunoglu, C., 2003, “Dominant Rock Properties Affecting the Penetration Rate of Percussive Drills”, International Journal of Rock Mechanics and Mining Sciences, Vol.40, pp.711–723.
• Karakuş, M., Tutmez, B., 2006, “Fuzzy and Multiple Regression Modelling for Evaluation of Intact Rock Strength Based on Point Load, Schmidt Hammer and Sonic Velocity”, Rock Mechanics and Rock Engineering, Vol.39(1), pp.45-57.
• Kidybinski, A., 1968, “Rebound Number and the Quality of Mine Roof Strata”, International Journal of Rock Mechanics and Mining Sciences, Vol.5, pp.283-291.
• Köken, E., Aydın, H., Özarslan, A., 2018, “S20KırılganlıkİndeksininKayaçlarınParçalanabilirliğiAçısındanİncelenmesi”, BilimselMadencilikDergisi, c.57 (özelsayı), ss.73-83. NTNU-Anleggsdrift, 1998, “Hard Rock Tunnel Boring, Norwegian University of Science and Technology”, Dept. of Civil and Transport Engineering, Report 1B-98.
• Poole, R.W., Farmer, I.W., 1978, “Geotechnical Factors Affecting Tunnelling Machine Performance in Coal Measures Rock”, Tunnels and Tunnelling International, Vol.10, pp.27-30.
• Schmidt, E., 1951, “A Non-Destructive Concrete Tester”, Concrete, Vol.59, pp.34-35.
• Shahriar, K., 1988, “Rock Cuttability and Geotechnical Factors Affecting the Penetration Rates of Roadheaders”, PhD thesis, Istanbul Technical University, p.241. Tarkoy, P.J., Hendron, A.J., 1975, “Rock Hardness Index”, US National Science Foundation report NSF-RAT-75-030.
• Ulusay, R., Hudson, J.A. (eds), 2007, “The Complete ISRM Suggested Methods for Rock Characterization, Testing and Monitoring: 1974-2006. Suggested methods prepared by the commission on testing methods”, International Society for Rock Mechanics (ISRM), Ankara, Turkey.
• Yagiz, S., 2009, “Assessment of Brittleness Using Rock Strength and Density with Punch Penetration Test” Tunneling and Underground Space Technology, Vol.24, No.1, pp.64-77.
• Yarali, O., Kahraman, S., 2011, “The Drillability Assessment of Rock Using the Different Brittleness Values”, Tunneling and Underground Space Technology, Vol.26, No.2, pp.406-414.